Defective apoptosis represents one of the six recognized cardinal features of cancer (Hanahan D, et al. 2000). Bcl-2-family proteins are evolutionarily conserved regulators of cell life and death. In humans, six anti-apoptotic members of the Bcl-2 family have been identified, including Bcl-2, BCl-XL, Mcl-1, Bcl-W, Bfl-1, and Bcl-B (Reed J C. 2000). Over-expression of Bcl-2 and some other anti-apoptotic members of the Bcl-2 family has been documented in human cancers (Reed J C. 1996). Given that investigational therapies targeting specific Bcl-2-family proteins or their encoding mRNAs are now in clinical trials, it is important to define which Bcl-2 family proteins are over-expressed in various types of cancer, so that appropriate targeted therapies can be matched to specific malignancies.